HbOThrace is an abnormal hemoglobin which is constructed by defective beta chains (Glu121-->Lys121). It mostly characterises the Muslim minority of the Thrace region. During the last 6 years, our department detected HbOThrace in 118 cases. Four groups were formed, the first consisted of cases of HbOThrace trait with normal iron and ferritin levels, the second of cases of HbOThrace hemoglobinopathy, the third of cases of HbOThrace/Hb beta zero hemoglobinopathy and the fourth of cases of HbOThrace trait with low iron and ferritin levels. The second, third and fourth group were compared with the first one. The conclusion is that the presence of HbOThrace leads to a mild hypochromic anemia, with no clinical findings, but the coexistence of beta zero gene or iron deficiency produces more pronounced laboratory findings and even clinically evident anemia.